Languages shape and are shaped by the environment, by the way the speakers experiences the world. There's the example by Franz Boas, regarding the many words Inuit might have for different kinds of snow [1]. Their language, in a very utilitarian manner, evolved to that state; and, of course, Inuit people's perception of the world is shaped by the fact that "snow" is not a single nor simple concept (they don't see "snow", they see a particular kind of snow with its associated characteristics). Wouldn't using English be a disservice to them, in their environment?

Besides the kind-of evolutionary argument (which might be downplayed on a globalised world), you'd have to consider the history and culture which languages carry. There are e.g. many recipes in my mother tongue which are named from historical and social context; all this would be somewhat lost in translation.

Obviously you have a point and there would be a lot of advantages on standardising on a language. The great issue is then on weighting pros & cons. Or greatest, even: being able to even begin to consider the cons. Can we really have an objective measure of how much we, mankind, would lose by turning all languages except English in dead languages?

Anyway, it doesn't matter much as the biggest obstacle is obviously political, not cultural.

[1] which was said to be a hoax, but after all not so much: https://www.washingtonpost.com/national/health-science/there...